


Asymptotic

by emrisemrisemris



Category: Mass Effect Trilogy
Genre: AU, M/M, ME3, indoctrination
Language: English
Status: Completed
Published: 2017-08-13
Updated: 2017-08-13
Packaged: 2018-12-14 23:30:34
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,402
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11793711
Author URL: https://archiveofourown.org/users/emrisemrisemris/pseuds/emrisemrisemris
Summary: Shepard came back from the Arrival mission with a shard of Reapertech in his head.





	Asymptotic

**Author's Note:**

> Originally posted [on Tumblr](https://emrisemrisemris.tumblr.com/post/163496281253/its-posting-week-for-the-july-meflashfanwork) for the July 2017 #meflashfanwork theme, "Running Out of Time".

 

**One year**

 

The thing that set the timer counting down was, when he reflected on it, very small.

It began as an angular shard a couple of centimetres long, a narrow triangle that stood out black on the scan image like a tiny delta-wing ship navigating some kind of tangled monochrome nebula. But the glowing white wisps surrounding it were not clouds of gas or smoke, but the shadows of living tissue, and the long axis of the delta lay neatly along the longitudinal fissure between the lobes of Shepard's brain.

Shepard sat in the locked medical bay with Mordin Solus on one side of the bed and Karin Chakwas on the other, and couldn't make eye contact with either of them. The little dark triangle drew the eye inexorably.

"How?" was all he managed to say, to Mordin.

The salarian shook his head. "Unlike any procedure in my experience. Surgical specialist here is Karin -"

"And I've never seen anything like it," Chakwas finished. She looked drawn, as if she hadn't slept. "Your skull is completely intact. There's no sign of any meaningful damage, let alone of serious brain surgery in the last two days." She gestured with her omni-tool, and the image changed from the flat image to a wireframe model of his brain, with the little triangle picked out in pulsating blue light. "The only theory either of us can come up with is that it assembled itself, in place, from some kind of smaller seed."

"Plenty of ingress points for seed, if sufficiently small and self-propelled," Mordin supplied helpfully. "Eye socket most likely. Similar to strategy used by certain varieties of parasitic worm."  
  
Chakwas gave him a look, and he stopped.

"If it was meant to grow," she resumed, "it's not doing so now. Completely inert. It may require some kind of signal from its parent organism. But we don't know."

"Reapertech," Shepard said.

He half expected some answering itch inside his skull, some recognition, but there was nothing.

"I can't think of anything else that _traitor_ Kenson would have wanted to put in you," Chakwas said, with a venom that Shepard had never heard in her voice before. "And while it's hard to get a good look, it seems to match the scan characteristics of other pieces we've encountered."

She called up a chart of the scan results: ultrasound, X-ray, molecular, MRI, mass effect, others he didn't recognise. A half-dozen images of the little black triangle rotated mesmerisingly against false-colour backgrounds, in perfect synchrony.

So very small.

Shepard watched them turn, and eventually asked, very quietly, "Can you get it out?"

"Doing it cleanly would be beyond my training." Chakwas shook her head. "And in any case _Normandy_ doesn't have the facilities for it. We'd need to get you to a proper hospital, somewhere civilised."

"Cerberus facilities could do it," Mordin said. "Advanced equipment. Remarkable resources. Discreet."

"I wouldn't trust Cerberus not to put in more than they took out," Shepard said bleakly. "And I can't just … go to a hospital with a piece of Reapertech in my head. The minute word got out, I'd lose my Spectre commission. Lose the _Normandy._ The Council may not believe me now, but if I turned up infected with the same stuff they pulled out of Saren -"

"What was left of him," said Chakwas quietly.

"- they'd arrest me on the spot."

"From what Admiral Hackett said," Chakwas pointed out, gently, "you're quite likely to get arrested anyway. At least temporarily, while the Defence Committee figure out what on earth they can say to the batarians."

"At least they'd be arresting me for something I actually _did_ ," Shepard snapped. "They can call me a war criminal, but I'm not a Reaper plant."  
  
"Yet," said Mordin. He shrugged, impervious to Shepard's glare. "Clearly not intended to kill. Possible purposes therefore limited to two. One, monitoring; two, indoctrination. Either way, compromised."

"No," Shepard whispered. "It's not doing anything. It's inert. She just _said_ it was inert."

"For the moment," said the salarian.

"Brain surgery's serious business." Shepard ignored Mordin and tried appealing to Chakwas. "If it was a bullet, stuck there, wouldn't taking it out do more damage than leaving it in?"

Chakwas gave him a look he couldn't read, but said "It would depend on the infection risk. Which is metaphorically exactly what we don't know here."

"So wait," Shepard said. "Monitor it. At least while we make the trip back to Earth."

"Very well," said Chakwas. Mordin said nothing.

  


**Six months**

 

"If you'd just step into one of these rooms, Commander -"

Chakwas herded him into one of the hospital ward's side rooms and into a chair, and shut the door. Wide shafts of the Citadel's artificial sunlight crossed the floor.

With the door safely locked, the doctor bent over Shepard with her omni-tool; orange fields flickered around his head.

"It's grown," said Chakwas, and it was no longer a triangle on the scan but a long bar, almost a blade. "No, Commander, don't say anything. You are going to wait here while I fetch Doctor Ayo from Major Alenko's room, and that - _thing_ \- is coming out of your head today."

Ayo proved to be Huerta Memorial's top human neurosurgeon. She looked over the scans, to Chakwas' quiet commentary (which did not, Shepard noticed, mention what the mysterious shard actually _was_ ) and eventually looked up gravely. "Certainly difficult, but absolutely possible. You'd be in hospital for three or four days. And then of course we'd need to monitor your recovery -"

"I have to get back into the field," said Shepard. "I have to go to Palaven -"

"Three weeks," Ayo said. "Minimum. Possibly more."

"Commander," Chakwas said mildly, "if you insist on returning to command in your present condition, I will not be party to it."

"I'm sorry," whispered Shepard. "I'm sorry. I have to go."

  


**Three months**

 

"Your prerogative," was all Mordin said when Shepard told him the shard had grown. He didn't look up from the console. The krogan woman - Eve - was in the mess hall; they were alone. The salarian waved one hand vaguely as he worked. "Right to refuse treatment is basic tenet of medicine; your skull, your mind, your decision."

"I didn't think you'd come around," said Shepard.

Mordin spun on the spot. "No such thing. Recognise your right to make the choice. Reserve the right to tell you it is dangerous. Stupid. Will only become worse."

"When we've finished the job on Tuchanka, that'll buy some time," Shepard said. "I'll go to Huerta Memorial, get it taken out. You have my permission to drag me if necessary."

"Good," said Mordin waspishly. "May take you up on it."

When they reached the Citadel, it was without Mordin, and it was to find Cerberus were there first.

 

 **  
** **Six weeks**

 

Rannoch's sky had more colours than an Earth sunset; there was something simultaneously very familiar and very alien about it.

Kaidan walked up beside him as he stood on the promontory next to Legion, and said nothing.

Legion knew. It had seen straight away, though had had the courtesy to wait until they were alone to ask him about it. He had no idea how to tell Kaidan.

  


**Three weeks**

 

"At my parents' place in Vancouver - drank more than a few beers on their balcony, looking over English Bay." Kaidan's eyes were faraway. "Beautiful view."

Shepard lined the words up in his head:

_Kaidan, I need to tell you something._

_I have a Reaper artefact in my head. It's been there almost a year._

"You know what though? I feel good about our chances. Lets me sleep better at night."

"You not been sleeping, Kaidan?"

They kept talking. Shepard said words, sincere words, and none of them were the ones he'd sat down to say.

He realised belatedly that as he'd come here to confess to Kaidan, Kaidan had come to confess to him, and now he couldn't say anything, couldn't poison it, not now.

"Someone?"

"You, Kaidan," said Shepard, and it was true, and it was right and it was good, and it still tasted bitter with the weight of what he hadn't said.

  


**Ten days**

 

**Five days**

 

**Two days**

 

**One day**

 

"I've known you for years," Kaidan said, with a kind of quiet wonder, "and I never realised you had blue eyes."

Shepard grinned. "I don't. It's the reflection off the fish tank. Makes everything in here look a little -"

The words died in his throat at Kaidan's frown.

"They're blue, Shepard. Did Cerberus give you a new set, or what?"

Shepard pushed past him without a word, and went to the bathroom mirror.

The reflection was unremarkable, mundane, the same familiar face he'd been looking into for years. Dark hair, growing out of its crop _already,_ scars that obstinately refused to close completely, a jawline he'd been complimented on, and those incongruous blue-grey irises. What was Kaidan making a fuss about?

The eyes. _His_ eyes. His eyes that were brown, and had been all his life - both his lives.

It took an effort of will to hold it in his head.

"Shepard?" said Kaidan behind him. "Shepard, are you -"

Shepard barely heard him.

He was struck, suddenly, by wondering if Saren Arterius had always had blue eyes.

  


**Twelve hours**

 

"It is too late," Dr Michel said bluntly. "If I try for surgery now, even with the help of EDI, you will die. The mass has made significant advances into your cerebellum, see -" she pointed "- and encased both optic nerves. Removing it will be fatal."

The mass on the scan was ugly and spiked now, a mess of unpleasant black planes and angles. Long excrescences like Reaper claws curved out from the main bulk following the track of the optic nerve, ending within the eye socket.

"How long has it been like this?" asked Kaidan softly.

He'd had to carry Shepard to the medbay. Shepard sat on one of the beds, and looked from Michel to Kaidan and back, and looked away. "I don't know. The shard's been in there about a year."

"A _year_?" said Kaidan.

He could practically see Kaidan counting backwards in his head. "It happened at Aratoht. Object Rho. You've seen the files -"

"You've had Reapertech in your head for a _year,_ and you didn't tell me?" Kaidan's clenched hands were sparking now, blue biotic artefacts fizzing into existence for a moment and then fading. "Shepard, have they been _following you_?"

"No. It's been inert. We know what Reaper signal looks like, and it hasn't been sending or receiving." Shepard reached for Kaidan's hand. "It's just … been there." His voice was rising, without his conscious input. "I meant to have it out on the Citadel. But I would've been out for weeks recovering. Or worse, if anyone realised what it was. Lost my commission. Lost the _Normandy._ " His voice cracked. "Never seen you again."

Above them, the scan image turned.

"You reckon it's too late to get it out?" Kaidan said to Dr Michel. She nodded.

Kaidan took Shepard's hand, and squeezed, and managed a brittle smile. "Guess all we can do is carry on."

  


**Six hours**

 

**Three hours**

 

**Ninety minutes**

 

Shepard stumbled to his feet in the London mud. Someone - James? - pulled him upright, took his weight; there was blood in his eyes, and even a half step towards the beam sent wrenching spasms through his legs and spine.

"I can't do it. _I can't do it._ " Shepard barely processed the ragged voice as his own. Overhead, the nearest Reaper turned its huge chassis towards them. He felt its attention on him like a searchlight; like a tractor beam; like the pin nailing an insect to the collector's mount.

Automatically, more muscle memory than will, he put one hand to his helmet radio and said "Fall back. It can't be done, We have to abort -"

The words went past vaguely, distantly, as if he was listening to somebody else, and then quite abruptly it filtered in to him that he _was_ listening to somebody else:

"This is Major Alenko." _Kaidan,_ Kaidan, screaming into his comm over the sounds of battle. "Countermand that. _Normandy,_ get the Commander off the field and to a hospital. I'm going in."

  


**Forty-five minutes**

 

Two Keepers were coming down the passage, picking their way delicately around the bodies as if they were so much rubble. Soon, Kaidan supposed, they would tidy them away.

His headset crackled.

_"Shepard?"_

"Alenko," he said to Anderson. "Shepard -"

He heard the indrawn breath even through the static. _"No. Surely -"_

It was Anderson's reaction that decided him, and Kaidan Alenko, who had never been a good liar, lied unhesitatingly. "He got hit badly. Couldn't go on."

 _"Guess it's you and me, then, Major,"_ said the old Admiral, as Kaidan stumbled onward through the blood.

  


**Twenty minutes**

 

"You too?" said Kaidan in stupefaction as the Illusive Man turned away from the console.

Black Reaper components wound their way over and through his jaw and neck, and his eyes glowed blue.

"So Shepard won't be joining us, then," he said, and there was an unpleasant emphasis on the _joining us_ that stuck in Kaidan's throat.

"No," said Kaidan, and shot him.

  


**Ten minutes**

 

The platform drifted upwards, Kaidan only barely conscious that it had even moved.

  


**Five minutes**

 

"You're not who I was expecting."

"I left Shepard on Earth," said Kaidan to the ghost. "You're a hallucination. Trust me. I've had plenty. Mostly little sparkly lights -"

"I am the Catalyst," said the thing that looked like Shepard's ghost.

  


**Two minutes**

 

**One minute**

 

"Make what happen?"

"You want to destroy us," said the hallucination, in Shepard's voice. "You can wipe out all synthetic life if you want. Including the geth. And most of the technology you rely on. Even you are partly synthetic."

Kaidan rubbed the back of his neck, feeling the familiar corners of his implant, dented, and crusted with blood.

"But the Reapers will be destroyed?"

Outside the windows of the Crucible, a Reaper took a hit from a turian dreadnought, far enough away that it could have been no more than a broken toy. One of its pincers spiralled away into pieces, into little sharp-edged black shards caught in silhouette against a cloud of smoke.

"Yes."  


**Thirty seconds**

 

**Fifteen seconds**

 

**Eight seconds**

 

**Four seconds**

 

"I love you, Shepard."

  


**Two seconds**

 

**One second**

 

*  


_An asymptotic function never reaches zero, although the graph bends infinitely close to it._

 


End file.
